Hello moped army fans, i have a Garelli Katia moped made in 1972. I have put all new engine oil in it, put in a new spark, mixed the fuel in the tank etc. As it is a pedal start moped i have to pull a wire to engage the clutch in the gearbox then the pedalling gets stiffer and then it fires. Trouble is it has a very weak chugging sound and as soon as i stop pedalling it cuts out?? I can find no other alternitive to this problem other than someone said the spark isnt sparking but it is, the other thing was to clean the carburettor. I have never done up a moped before so im not sure how to clean it. Someone told me to adjust some screws, i did and its still the same. Can anybody help???